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Silver is A Broad Spectrum Anti-Viral

Paul Maher, MD MPH, 3/22/2019

Silver has been understood from antiquity to have anti-infective properties.i In our time various silver

based preparations and formulations are commonly employed as wound dressings, as treatment for

topical infections and for water purification. The anti-fungal,ii anti-protozoaliii and broad spectrum

anti-bacterial propertiesiv,v of silver have been well-researched and documented in medical studies.

Somewhat more recently the broad spectrum anti-viral activity of silver has become more widely

recognized and documented. This review will examine the peer-reviewed medical literature relating to

the anti-viral properties of silver with specific attention paid to anti-viral activity of silver against

enveloped viruses and, in light of the recent COVID-19 viral pandemic, what studies may be available

specifically concerning the activity of silver against coronaviruses.

Before beginning a brief note concerning terminology is appropriate. The majority of studies

referenced, refer to the activity of “nano” particles of silver. Nanosilver is a somewhat nebulous term,

but generally is seen to refer to silver particles with diameters in the 10-100 angstrom (nanometer)

range or sometimes 1-100 angstroms. Such silver nanoparticles may be generated by a variety of

chemical, biological and physical means, to include electrolysis. Particles of silver of sufficiently small

diameter, nano particles, when placed in water will, due to Brownian motion and the repelling action of

like charges, remain dispersed in solution for a long time to indefinitely. Such a solution is termed a

colloidal solution of silver particles, (colloquially, “colloidal silver”) . As silver, if unbound to other

elements has a positive charge one also occasionally hears the term “ionic silver” employed.

In 1975 Chang et al.vi, documented in-vitro activity of silver sulfadiazine against Herpesvirus hominis

virus, noting drug activity was proportional to duration of exposure and concentration of silver

sulfadiazine. Herpesvirus is an enveloped DNA virus. Similarly, in 1999, Stozkowskavii and

Wroczyńska-Pałka researched the activity of silver sulfathiazole against Herpes virus stating, “This

drug suppresses or completely inactivates the infectivity of virus. The antiviral effect is directly related

to concentration of the drug and duration of exposure.” The researchers also noted a similar activity

with silver nitrate while sulfathiozole alone, without silver, did not show anti-viral activity.

Human immunodeficiency virus (HIV), the well-known cause of AIDS, is an enveloped, RNA

retrovirus virus. Viral cell entry is mediated by the interaction of a glycoprotein, gp120, embedded in

the viral membrane with the cluster of differentiation (CD4) receptor protein found on the surface of

immune cells. In 2005, Elechiguerra et al. published, “Interaction of silver nanoparticles with HIV-

1”.viii Silver nanoparticles produced from three different approaches were found, in-vitro, to prevent

cell entry of the HIV virus. The authors state, “For all three nanoparticle preparations, at silver

concentrations above 25 μg/mL, viral infectivity was reduced to an extent that it could not be detected

by syncytium formation”. Through electron microscopy scanning studies the authors concluded that

particles in the size range of 1 to 10 nanometers were binding to the virus and responsible for

preventing viral cell entry. Further, the binding of the silver particles was not random but was selective

for the protruding gp120 glycoproteins most likely in the area of dilsulfide bonds on this protein. The

resulting steric hindrance from the attached silver prevented viral entry into the cell. While, as will be

noted later, there appear to be additional mechanisms of anti-viral action mediated by silver, this

research, in addition to documenting the absence of HIV viral cell entry, provides a plausible

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mechanism of action for how silver might block cell entry of enveloped viruses. COVID-19 is an

enveloped virus whose cell entry is mediated, per early research, by interaction of the viral membrane

spike glycoprotein with the Angiotensin II Converting Enzyme(ACE II) receptor protein.ix

Hepatitis B is a small double stranded, enveloped DNA virus. In 2009 Lu et al.x reported the results of

in-vitro study examining the interaction of silver nanoparticles and the hepatitis virus. These silver

particles were created chemically from silver nitrate and designed to have particle diameters of either

approximately 10 nanometers or approximately 50 nanometers. The researchers found that both sizes

of particles reduced extracellular virus formation by greater than 50%. While silver did not have an

effect on intracellular viral DNA, it did inhibit the formation of viral RNA from this DNA template, a

necessary step in infection. The authors conclude, “Silver nanoparticles could inhibit the in vitro

production of HBV RNA and extracellular virions. We hypothesize that the direct interaction between

these nanoparticles and HBV double-stranded DNA or viral particles is responsible for their antiviral

mechanism.” As silver was found to inhibit formation of messenger RNA post viral infection, this

would indicate a second possible mechanism of action of silver against viruses in addition to the

blockage of viral cell entry, as the authors speculate, perhaps mediated by interaction of silver with

viral DNA.

Human respiratory syncytial virus (RSV) is an enveloped RNA virus. In 2008 Sun et alxi reported

results of in vitro research finding that PVP coated silver nanoparticles at low concentrations inhibited

RSV infection by 44%. Monkeypox virus is an enveloped RNA virus within the orpthopox virus

genus. While the virus generally infects animals it may cause zoonotic infections in humans leading to

a disease somewhat similar in presentation and course to smallpox. Rogers et al. reported results on

research examining inhibition of monkeypox viral plaque formation from exposure to silver

nanoparticlesxii. Nano particles created from plasma gas synthesis and polysaccharide-coated silver

nanoparticles in ranges from 10 to 100 nanometers were examined at dosages ranging from 25 – 200

ug/ml. No concentration of nanosilver exhibited cytotoxicity at the dosages examined. Silver

nanoparticles of 55 nanometers and polsaccharide coated silver particles of 25 nanometers

demonstrated a statistically significant dose dependent decrease in viral plaque formation. Other

particle sizes did not lead to statistical significance with some sizes and dosages leading to non-

significant increases in plaque formation.

Following the earlier work of Chang and Stozkowska, Baram-Pinto et al.xiii created silver nanoparticles

capped with mercaptoethane sulfonate and studied their effect on Herpes simplex virus. These silver

nanoparticles led to the blockage of viral entry into cells and “prevention of subsequent infection”.

Mercaptoethane sulfonate alone showed no anti-viral activity. Vijayakumar and Prasad reported on

results of creation of silver nanoparticles embedded in a carbonaceous matrixxiv “This carbonaceous

matrix embedded silver nanoparticles showed antimicrobial properties against both bacteria (Gram-

positive and Gram-negative) and virus (M 13 phage virus). The bactericidal effects were noticed even

after washing and repeated exposure of these carbon supported silver nanoparticles to fresh bacterial

cultures, revealing their sustained activity”. Similarly, De Gusseme et al.xv created silver nanoparticles

utilizing a bacterium as both a reducing agent and silver matrix, resulting in nanoparticles in the 0.9-

11.2 nanometer range. This nanosilver when applied to a carbon filter led to a 3.8 log reduction in

water with murine (mouse) norovirus. The authors conclude, “This is the first report to demonstrate

the antiviral efficacy of extracellular biogenic Ag0 and its promising opportunities for continuous

water disinfection”.

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Arenaviruses are a family of non-enveloped RNA viruses responsible for a variety of serious viral

hemorrhagic fevers. Speshock et alxvi examined the interaction of silver nanoparticles with the Tacribe,

arenavirus. Silver did not inhibit viral entry into Vero cells grown in culture for these non-enveloped

viruses. However, silver nanoparticles in the size range of 25-50 nanometers “dramatically reduced”

viral RNA expression leading to a significant reduction in progeny virus. The authors conclude,

”Silver nanoparticles are capable of inhibiting a prototype arenavirus at non-toxic concentrations and

effectively inhibit arenavirus replication when administered prior to viral infection or early after initial

virus exposure”.

Silver has been examined by multiple researchers for its effect on influenza virus. Mehrbod et alxvii

reported nanosilver inhibited viral entry of this enveloped virus. Xiang et alxviii reported that silver

nanoparticles in the 10 nm range inhibited influenza A as evidenced through a variety of assays. For

instance, the hemagllutination assay is a commonly employed method for quantifying the

concentration of influenza virus. The authors state, “In the presence of silver-nps, the ability of H1N1

influenza A virus to agglutinate erythrocytes was either reduced or completely inhibited”. Mori et al.xix

created silver nanoparticles complexed with chitosan (lobster shell) with particles sizes ranging from

3.5 to 12.9 nanometers. All sizes of particles exhibited a dose dependent inhibition of influenza A,

while chitosan alone demonstrated no anti-viral activity.

Since 2013 research on the antiviral properties of nanosilver has increased greatly. Adenoviruses are

non-enveloped DNA viruses that are a frequent cause of the common cold. Chen et alxx report a dose

dependent decrease in adenovirus type 3 viral DNA in cultures treated with nanosilver, concluding,

“the present study indicates silver nanoparticles exhibit remarkably inhibitory effects on Ad3 in vitro”.

Vaccinia virus, a large enveloped DNA virus closely related to Smallpox virus, has been well studied

as the viral agent responsible for the eradication of smallpox disease through vaccination. Trefry et

al.xxi report that 25-nm silver nanoparticles inhibited viral entry into cells, “The silver nanoparticles

caused a 4- to 5-log reduction in viral titer at concentrations that were not toxic to cells. Virus was

capable of adsorbing to cells but could not enter cells in the presence of silver nanoparticles”.

Xiang et al.xxii reported results on research into silver nanoparticles and human H3N2 influenza virus.

The unconjugated nanosilver was created chemically through an oxidation-reduction reaction of silver

nitrate with sodium carbonate and tannic acid. No information is provided on the resulting silver

particle sizes. At dosages from 6.25 to 50 ug/ml there was no observed cytotoxicity to the examined

cell lines. Silver nanoparticles were shown to decrease to a statistically significant degree growth of

influenza virus as indicated by the hemagglutination assay and likewise to decrease cell apoptosis

(death). Electron microscopy studies found destruction of morphological viral structures through

interaction with silver particles starting from 30 to 120 minutes post exposure. This study is also

notable for the report of animal in-vivo results. Mice inoculated intranasally with nanosilver

demonstrated significantly enhanced survival after exposure to H3N2 influenza virus, specifically none

of the control group mice survived while 75% of those inoculated with nanosilver intranasally

survived. Treated mice also showed “lower lung viral titer levels and minor pathologic lesions in lung

tissue”.

Gaikwad et al.xxiii reported on in-vitro results of nanosilver’s effects against Herpes simplex virus types

I and II and Human Parainfluenza virus type 3. Nanoparticles in this instance were produced from a

fungus based approach. Average particle size was estimated to vary from 20 to 50 nanometers. The

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Vero cell assay was used to determine cytotoxicity of silver to cells. Antiviral activity was measured at

concentrations ranging from 0.1, to 10 μg/mL by observing the number of viral plaques in Vero cell

monolayers as compared to controls. Cell cytotoxicity was not observed at the concentrations

evaluated. Treatment showed a consistent decrease in replication efficiency for Herpes simplex type I

and Parainfluenza virus and a minor effect on Herpes simplex type II virus. Interestingly, the particular

fungal species used in preparing the nanosilver had a considerable effect on anti-viral activity. The

authors speculate that the differences may be due to variations in particles size and/or zeta potential

(charge) from samples prepared from different fungi. They write, “From the present study it was

observed that AgNPs were capable of controlling viral infectivity, most likely by blocking interaction of

the virus with the cell, which might be dependent on the size and zeta potential of the AgNPs”.

Moving on to 2014, the following study, “Inhibitory effect of silver nanomaterials on transmissible

virus-induced host cell infections” by Lv et al.xxiv is notable in the present context. The authors state

that, “transmissible gastroenteritis virus (TGEV) is an economically significant coronavirus that can

cause severe diarrhea in pigs”. The authors note that human corona viral infections including the

recent MERS and SARS outbreaks are a public health concern and so the researchers chose TGEV

Coronavirus as a model for human Coronavirus infection. Four types of silver nanoparticles were

examined to include silver nanowires of 60 and 400 nanometers and silver nanoparticles of 10 and 20

nanometers. Swine testicle (ST) cells were cultured in Dulbecco's modified Eagle's medium and cell

viability determined using the “MTT” assay. PCR, Western Blot, immunofluorescence and flow

cytometry assays were also performed. The silver nanowires and 20 nm nanosilver particles decreased

cell apoptosis (death) from corona virus infection. The MMT assay demonstrated that these three silver

formulations also led to a dose dependent reduction in viral titers. Interestingly, the 10 nm silver

particles did not show an anti-viral effect. However the Polyvinylpyrrolidone capping agent used as a

stabilizer was 4 fold higher in the 10 nm silver particles as compared with the 20 nanometer particles

and the authors speculate this may have had an effect on the anti-viral activity as compared with the

other three silver formulations. Through further research the authors find that one plausible mechanism

of action for silver’s anti-viral activity in this study was from interaction with the p38/mitochondria-

caspase-3 signaling pathway which plays a role in mediation of cell apoptosis.

The authors conclude from their research, “Our data indicate that Ag NMs are effective in prevention

of TGEV-mediated cell infection as a virucidal agent or as an inhibitor of viral entry”.

Hu et al.xxv confirmed the anti-viral activity of silver nanoparticles against Herpes simplex virus type II

as evaluated through plaque formation assay and MMT assay stating, “Therefore, 100 μg/mL Ag-NPs

could completely inhibit HSV-2 replication. Ag-NPs at nontoxic concentrations were capable of

inhibiting HSV-2 replication when administered prior to viral infection or soon after initial virus

exposure.”

Khandelwal et al.xxvi demonstrated that silver nanoparticles derived from silver nitrate and with a size

range of 5-30 nanometers at a nontoxic concentration inhibited replication of a Morbillivirus that may

afflict livestock. Orlowski et al.xxvii reported that tannic acid modified silver nanoparticles in the size

range of 13 to 46 nanometers inhibited Herpes simplex type II viral infection in-vitro and in-vivo in

mice. Closing out 2014, Swathy et alxxviii published research on a surprising synergism between silver

nanoparticles and carbonate ions. The researchers, “discovered that 50 parts per billion (ppb) of Ag(+)

released continuously from silver nanoparticles confined in nanoscale cages is enough to cause

antimicrobial activity in conditions of normal water.” By way of context, sodium fluoride is often

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added to water supplies at a level of 1-2 parts per million, so this is a concentration of silver some

1/20th to 1/40th that of added fluoride. The authors go on to state, “the antibacterial and antiviral

activities of Ag(+) can be enhanced ~1,000 fold, selectively, in presence of carbonate ions “ While not

discussed by the authors baking soda is an extremely inexpensive source of carbonate ions.

Sujitha et al.xxix 2015 reported success in controlling Dengue fever viral infection in-vitro with silver

nanoparticles. Treatment with 20ug/ml silver nanoparticles led to a greater than 4 log reduction in viral

titers after six hours. “AgNP were highly effective against the dengue vector A. aegypti”. Elbeshehy et

alxxx report that silver nanoparticles in the size range of 72-92 nanometers show activity against Bean

Yellow Mosaic Virus. Fatima et alxxxi report in 2106 that silver nanoparticles created using

Cinnamomum cassia as a reducing agent effectively and non-toxically inhibited H7N3 Influenza A

virus infection of a cultured Vero cell line. Somewhat similarly, Yang et al.xxxii also report in 2106 that

silver nanoparticles using curcumin as a reducing agent showed a, “highly efficient inhibition effect

against respiratory syncytial virus (RSV) infection, giving a decrease of viral titers about two orders of

magnitude … no toxicity was found to the host cells”. Bekele et alxxxiii examined the activity of silver

nanoparticles of 10, 75, and 110 nanometers against feline calicivirus. At dosages of 50 and 100 ug/ml

the 10 nanometer particles, “inactivated the FCV (feline calicivirus) beyond the limit of detection”.

The larger 75 and 110 nanometer particles did not show anti-viral activity. Borrego et al.xxxiv report

that a proprietary formulation of silver nanoparticles was effective in preventing Rift Valley fever viral

infection of a Vero cell line.

Also in 2016 Chen et al.xxxv created silver nanoparticle impregnated graphene oxide sheets. This

material was tested for activity against infectious bursal disease virus and feline coronavirus (FcoV).

The silver impregnated sheets reduced viral infection by feline coronavirus by 25% as compared to

16% for graphene oxide alone. While certainly not a dramatic result this is a second confirmatory

study that silver has anti-viral activity against viruses of the corona virus family.

Another interesting study from 2016 was published by Li et al.xxxvi. The researchers describe

“decorating” the surface of the antiviral drug oseltamivir (Tamiflu) with silver nanoparticles and

comparing the in-vitro efficacy of this combination to silver alone and oseltamivir alone for ability to

inhibit H1N1 influenza. Quoting the researchers, “Compared to silver and oseltamivir, oseltamivir-

modified AgNPs (Ag@OTV) have remarkable inhibition against H1N1 infection, and less toxicity was

found for MDCK cells by controlled-potential electrolysis (CPE), MTT, and transmission electron

microscopy (TEM). Furthermore, Ag@OTV inhibited the activity of neuraminidase (NA) and

hemagglutinin (HA) and then prevented the attachment of the H1N1 influenza virus to host cells.” This

finding is significant in that oseltamivir is one of the drugs currently being researched and utilized as a

possibly useful treatment for COVID-19 infection. In this study regarding influenza virus, silver was

seen to have a synergistic effect with oseltamivir.

While there are further positive studies of anti-viral activity from 2017 to the present, due to constraints

of time the literature review will be truncated here. It is trusted that to a reasonable reader the above

suffices to convincingly make the case that silver is a potent and broad spectrum anti-viral. It should

also be noted that by no means have these studies been “cherry picked”. While there are some studies

with less dramatic findings, some studies where some of the particular dosages, particle sizes or

formulations in a given study were not effective, in this literature review I have not seen a single article

reporting absence of anti-viral activity against any virus that was researched.

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The above research was almost uniformly in-vitro (test-tube) studies, it is unfortunate that more in-vivo

data is not available at this time for this very promising anti-viral. Further, many issues relating to the

in-vitro studies, how do we prevent the silver from clumping in the growth media we are using, for

instance, are not at all directly applicable to the in-vivo system, where the question would instead by

what is the behavior of nanosilver in the albumin rich milieu of blood plasma.

There are literally dozens of approaches to generating nanosilver with one recent article reviewing a

number of physical, chemical and biologically oriented approachesxxxvii. One means of generating

nanosilver has been conspicuously absent from the studies published in the literature to date, namely

the way the great scientist and experimenter, Michael Faraday first created colloidal metals nearly two

hundred years ago, through electrolysis. This approach is not at all complicated, for instance to create

colloidal silver one would start with two wires or strips of 99.9% pure silver. One silver wire is

connected to the positive of a DC voltage source, say a nine volt battery, the other wire to the negative

of the battery. The two wires, and only the wires, are placed in water separated by a distance of 1/8th

to one half inch to allow the water to act as a resistor. Over the course of a few minutes a cloud of

microscopic silver is seen to appear in the water. Over time this silver would eventually electroplate on

the negative electrode, however, due to the like positive charges on the small silver particles, and the

Brownian motion of water, the majority of the silver stays in solution as a colloid. If one has a total

dissolved solids meter, costing perhaps 20 dollars, one can document the concentration in parts per

million of colloidal silver as the process proceeds. If one starts with tap water with 200 ppm dissolved

minerals and impurities when one reads 220 ppm dissolved solids one knows one has 20 ppm silver in

that water. In a pinch, if one has two 99.9% pure silver dollars, one could also use those to create

colloidal silver following the same procedure. Two silver wires weighing only a few grams and

costing a few dollars could produce literally tens of gallons of colloidal silver before themselves being

dissolved through electrolysis. This treatment would cost pennies per day.

When one sees a slight cloudy white tinge to tap water, this is generally a concentration in the range of

10-40 ppm. Hence, even if one does not have a dissolved parts meter one can eyeball a reasonable

concentration by observing a very slight cloudy tinge to the water. If, as will be discussed further, one

uses distilled water one will see a slight cloudy yellow tinge to the water instead of whitish, again

consistent with a 10-40 ppm concentration.

Peter Lindemann, PhD, has published non peer-reviewed results of characterization of silver particles

produced through electrolysis.xxxviii By electron microscopy characterization, low voltage electrolysis of

silver in tap water is reported as generating particles in the size range of 50 to 150 nanometers. While

on the large size of those particles showing efficacy in the previously reviewed literature, this is within

the size range of particles that showed anti-viral activity in some studies. Silver generated by

electrolysis in distilled water was found to have a particle size of around 4 nanometers. This smaller

particle size, secondary to the Tyndall effect shows a yellowish tinge, reflective of the small particle

size. As smaller particle sizes were generally associated with greater antiviral activity in the above

review, I concur with Dr. Lindemann’s position that ideally one might wish to create colloidal silver

with distilled water. There is a caveat to that position however, which again refers to use of silver in-

vivo. Unfortunately, the pharmacodynamics and pharmacokinetics of nanosilver are for the most part

uncharacterized in peer-reviewed literature at this time. Nonetheless, one point is fairly obvious.

About the first thing colloidal silver taken by mouth will encounter is stomach acid. Stomach acid is

primarily hydrochloric acid. Silver dissolves in hydrochloric acid. Hence, while colloidal silver

created with tap water has a slightly larger particle size than one might wish when considering the

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previous literature, it would seem a fairly safe bet that due to the activity of hydrochloric acid on silver,

the particle sizes reaching the blood stream would comprise a range consisting of particles smaller than

those ingested. More simply, I would say, do not despair about making useful anti-viral colloidal silver

if one doesn’t have distilled water. While it would be nice to have distilled water, clinically the two

approaches may likely yield similar results. I would further recommend Dr. Lindemann’s write-up on

this topic as a useful guide to creating colloidal silver. Again, however, do not be intimidated, one

doesn’t have to “overthink” this. Take two strips of pure silver connect them to a nine volt battery stick

the strips (not touching each other) in a glass of water. Make sure only silver is in the water as one is

not trying to create colloidal alligator clip. In 2-5 minutes or so with tap water one will see a slightly

cloudy tinge, one is done. If using distilled water at nine volts this will take 1-2 hours and one will see

a slight yellowish tinge. Dr. Lindemann mentions using, I believe, a tablespoon or two of 10-20 ppm

colloidal silver, I am perhaps a bit more radical as every couple weeks I brew up 8 ounces of 10-20

ppm colloidal silver made from twice filtered tap water and gulp it down, it is some of the best tasting

water you will come across. I also make a second glass and pour it through a carbon (Britta) water

filter and use that filter for my drinking water for the next two weeks.

Colloidal silver, made from a variety of means has been used as a health tonic by hundreds of

thousands of people by this time. The primary, and only that I am aware of, concerning health side

effect reported from this usage appears to be a very rare occurrence of bluish skin discoloration known

as argyria. While it is arguable, whether argyria is seen only with ingestion of silver salts such as

silver nitrate or also with prolonged use of colloidal silver, yes, if one drank gallons of 100 ppm

colloidal silver for years and never looked in a mirror, one might theoretically find a serious problem

with skin discoloration. This side effect might be compared with the, still widely used antibiotic,

gentamicin, which causes a rare, acute, sometimes irreversible hearing loss. Further, some

commonsense is in order, two strips of wire weighing a few grams will suffice to make tens if not

hundreds of gallons of colloidal silver before themselves fully dissolving. This is not at all like a child

munching down chips of lead based paint, this is a very, very small amount of silver, likely a dose

orders of magnitude less than the 50 mg of elemental zinc one might take, and correctly so, as a

supplement without a second thought.

In addition to a reasonable safety profile established through years of use by at minimum hundreds of

thousands of people, there are numerous testimonies of health benefits, sometimes dramatic, from

individuals using colloidal silver made electrolytically from tap water and possibly distilled water as

well. I will not delve into this literature as there are I realize some readers who might find the

presentation lessened if evidence is expanded outside of the peer-reviewed literature. I would just pose

as a philosophical question, if one can identify the identity of an individual patient and has no reason to

suspect a financial or other bias to their reporting, should the patient’s description of their own

symptomatology and disease course be considered more or less authoritative than the second hand case

report written up by their physician in a medical journal? As a corollary, who would be expected to

more often have a financial or emotional bias to distort results of a health intervention, a patient or a

health practitioner? These are questions far outside the scope of this write-up except to note that the

evidence presented has been solely from the peer-reviewed medical literature to keep from turning

away those purists who feel strongly that this is all that should be taken into consideration.

Lastly, in addition to taking colloidal silver internally, if one knew they were not going to be able to

wash their hands with soap and water for a time, applying colloidal silver water topically might help to

prevent spread of disease in the same way that silver impregnated wound dressings are used as anti-

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infectives for difficult to treat wounds. One might also consider making a concentrated glass of

colloidal silver and pouring it into the end of a wash cycle for laundry, or simply soaking laundry in

colloidal silver before drying, so as to have silver impregnated clothing. The literature for silver as an

effective antibacterial against both gram positive and negative bacteria is more voluminous than what

has been presented here for its’ anti-viral activity. It bears noting that what often is fatal for someone

acquiring a viral pneumonia is the injured lungs developing a superseding bacterial infection which the

patient in a weakened condition is unable to fight off.

In summary, silver is well-documented in the peer reviewed medical literature to be a broad spectrum

anti-viral, silver is also a broad spectrum anti-bacterial. Two in-vitro studies have documented activity

of silver against animal corona viruses. In the current context of COVID-19 spread it is urgent and

imperative that health researchers and authorities examine the in-vitro and in-vivo activity of silver

against this novel corona virus. One reasonable mechanism of action by which silver interferes with

viral entry is by binding to the thiol residue disulfide bridges of surface glycoproteins of enveloped

viruses as documented in the literature. Silver has demonstrated highly selective viral toxicity in-vitro.

Colloidal silver, used appropriately and reasonably, has a track record of years of safe use. Colloidal

silver with particle sizes identical to those showing activity in the medical litrature may be generated

cheaply and easily through electrolysis.

One should not provide a false hope, one is also and perhaps more culpable, for failing to disclose a

reasonable hope. Colloidal silver may or may not be effective against COVID-19, those studies need to

be performed, the above provides a reasonable hope that it could be effective. Hospitals overwhelmed

with viral illness will be hard pressed to provide appropriate care to all but the most ill, while someone

with a common cold who goes to a hospital to be tested for COVID-19 runs a very high risk of now

being infected with this highly contagious bug even if they weren’t before they visited the hospital.

Colloidal silver has a track record of safe use, costs a couple cents or less for per eight ounce glass, and

can be made in a few minutes with a nine volt battery and a couple strips of 99.9% pure silver. Perhaps

the most appropriate question one might ask is, what have you got to lose?

Correspondence: PDMaher123@gmail.com

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